Issue |
Reprod. Nutr. Dev.
Volume 46, Number 4, July-August 2006
Symposium: Influence of nutrition and socio-sexual context on reproduction and survival of the young in goats and sheep
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Page(s) | 447 - 460 | |
DOI | https://doi.org/10.1051/rnd:2006024 | |
Published online | 07 July 2006 |
DOI: 10.1051/rnd:2006024
Endocrine and metabolic factors involved in the effect of nutrition on the production of colostrum in female sheep
Georgett E. Bancheroa, Raquel Perez Clarigetb, Roberta Bencinic, David R. Lindsayc, John T.B. Miltonc and Graeme B. Martinca National Institute of Agricultural Research, INIA La Estanzuela, Ruta 50 Km 12 Colonia, Uruguay
b Animal and Forage Sciences Department, Faculty of Agriculture, Avda. E. Garzón 780, 12900, Montevideo, Uruguay
c School of Animal Biology, The University of Western Australia, Crawley 6907, Australia
(Published online 7 July 2006)
Abstract - We investigated the physiological relationship between
diet during pregnancy and colostrum production in ewes to test the
hypothesis that for ewes that are in low body condition, with low fat
reserves, the food supply will be the main source of energy for colostrum
synthesis. To this end, we measured the amount of colostrum accumulated by
ewes under two levels of nutrition. We also measured the circulating
concentrations of metabolites and hormones associated with lactogenesis
(-hydroxybutyrate, glucose, progesterone, prolactin, cortisol,
growth hormone, leptin, insulin and insulin-like growth factor-I) Ewes were
either under-fed at 70 (n = 15) or well-fed at 110% (n = 10) of their daily
metabolisable energy requirement during the last two months of
pregnancy. Colostrum accumulation up to parturition was
g for
under-fed ewes and
g for well-fed ewes. After birth, under-fed
ewes produced less colostrum than well-fed ewes but the difference was no
longer significant. The level of nutrition also influenced the plasma
concentrations of hormones and metabolites related to lactogenesis.
Progesterone concentrations decreased before lambing in all animals but in
under-fed ewes the fall appeared to be too small to initiate the onset of
colostrum production.
-hydroxybutyrate concentrations were higher in
under-fed than in well-fed ewes, suggesting that the under-fed ewes were
mobilising more adipose tissue but they still did not meet their ME
requirements for colostrum production. We concluded that, in underfed ewes,
there are insufficient nutrients for adequate lactation and the hormone
regime is inappropriate for good udder development and colostrum synthesis.
Key words: udder development / lactogenesis /

Corresponding author: banchero@inia.org.uy
© INRA, EDP Sciences 2006